Creating a bash based restricted shell

Applications Programming
1

Hello.

I need to write a command line interface that can be invoked either directly from the shell (command sub-command arguments), or as a shell that can process sub-commands.
i want to use bash auto completion for both scenarios.

example: lets say my CLI module is called 'mycli' and there are 3 sub commands: add, list, delete.

for the first type of usage, one would write from the prompt:

ubuntu@ubuntu:/$mycli add -name myname

for the second type of usage, one would do the following:

ubuntu@ubuntu:/$mycli
MYCLI>add -name myname
MYCLI>list

i know how to create a bash autocomplete for the first example. but don't know how to create a shell-like prompt that will use bash auto complete for sub command processing.

any suggestions?

2

bash uses the readline library to implement the auto complete, line up, emacs keys editing in commands.

There is a Perl "scriptable" equivalent, Term::Readline which may provide a suitable easily programmable shell for you

1 Like
3

unfortunately, although the readline library would probably work, it's license mandates that any software using it will be free. and the product i'm developing isn't, so i probably can't use it.

any other suggestions?

4

Hi.

The tcl/tk package may be of some use. The sense of the license is left as an exercise: Tcl/Tk Licensing Terms

Searching for completion at the tcl/tk site brings up a about 2K hits.

Best wishes ... cheers, drl

5

If readline would work, but its license is a dealbreaker, have a look at the editline library (BSD license).

Regards,
Alister

6

Hi, Alister.

Good alternative for many features. However, at a quick glance I didn't see anything for completion. I looked at editline(3) - Linux man page and Man Page for editline (freebsd Section 3) - The UNIX and Linux Forums -- is there a betteer version or did I just miss reading the page? ... cheers, drl